Percutaneous revascularization (PCI) of chronic total occlusions (CTO) is a technical challenge with a lower success rate than the rest of angioplasties. Knowing the predictors of technique failure and selection of candidates with the largest benefit would improve the results. Hypothesis: the use of nuclear magnetic cardio resonance (CRM) and multidetector computed tomography (MDCT) allows to detect those patients with greater clinical benefit and to identify the morphological characteristics of occluded segment that are associated with failure in recanalization. Objectives: 1) determine the viability/ myocardial ischemia and its reversibility after opening the vessel, 2) determine the morphological predictors of failure of PCI and 3) evaluate the clinical effectiveness of the procedure in the follow-up. Design: Patients with one or > CTO meeting the inclusion criteria underwent MDCT and CRM. During the follow-up, after revascularization, was scheduled a CRM at the 9th and angiography at 12th month. Methods: Prospective, single-centre study of 69 consecutive patients with 1 or > CTO and clinical indication for revascularization. Left ventricular function, myocardial viability and inducible ischemia were analyzed by CRM. Anatomical features, plaque composition and distribution and density of calcium in the CTO body were characterized by MDCT Results: Population: age 63. 4 ± 9. 6 years, 84% men. Cardiovascular risk factors: hypertension 78%, 77% dyslipidemia and 38% diabetes mellitus. Previous documented myocardial infarction 42%. 77 lesions were analyzed: length occluded segment 19. 9 ± 14. 3 mm, estimated duration of occlusion 47 ± 62 months. The success rate of revascularization was 62%. Leading cause of failure: inability to cross the lesion with any guide wire. The most powerful angiographic factor of failure was the presence of a severe curve between the occlusion and the proximal patent vessel [OR = 3. 8 (95%,1,2-12) p = 0. 02]. The MCT analysis revealed as the only predictor factor of failure an arch of calcium that affected more than 50% of the vessel circumference in the proximal (p=0. 04) and middle (p=0. 03) segment of the occlusion. CRM at the follow-up shows significant improvement in the number of ischemic segments (0. 027 vs. baseline 1. 54 ± 2. 5, P = 0. 003) and in the regional contractile function (hypo/akinetic/dyskinetic segments 2 ± 2 vs 1. 6 ± 2. 1 p = 0. 027). Angiography: restenosis rate of 18%. It's reported one very late stent thrombosis (1554 days). Major adverse cardiac events during follow-up (median 1457 days) occurs in 4 patients (8. 9%) in the successful revascularization and 3 (12. 5%) in the failure group, p = 0. 69. Conclusions: CRM is a suitable instrument in the selection of patients who will benefit from a revascularization of the CTO. MDCT identifies the presence of a calcium arc of > 50% of the circumference of the vessel at the proximal border and the middle part of the body CTO multiplying by a negative factor > 3 the possibility of failure. The clinical outcome is favourable with rates of major cardiac events, restenosis and stent thrombosis expected.